As the COVID-19 pandemic continues to develop, new information about the virus is being learned by doctors and researchers each week. Dr. Raghavendra Tirupathi, Medical Director of Keystone Infectious Diseases, has answered some frequently asked questions about the latest information related to the testing and diagnosis of coronavirus.
How is COVID-19 Diagnosed?
The COVID-19 infection is diagnosed by a test called polymerase chain reaction. Samples are taken from places like the back of the nose or mouth, or deep inside the lungs – places that are likely to have the virus. After the sample is collected, a process of extracting particles of the potential virus takes place. Those particles are then tested by a procedure that involves converting the particles to DNA and using a fluorescent signal to test for a viral sequence.
Anyone with symptoms of COVID-19 should contact their primary care provider to see if they need to be tested. These symptoms include fever, chills, cough, shortness of breath, sore throat, loss of sense of smell or taste, diarrhea and excessive muscle aches or body pains.
What Is An Antibody Test?
Antibodies are proteins produced by your body to help fight off infections in response to foreign invading particles, such as viruses. Antibody tests are blood tests which check your blood for antibodies. This shows whether you had a previous infection with, or exposure to, the virus. Antibodies may not be found in someone who has a current COVID-19 infection depending on the timeline of infection and when the test was performed. These tests should not be used to diagnose someone as being currently sick with COVID-19.
What If You Test Positive On The Antibody Test?
A positive test shows that you have antibodies which likely came from an infection of SARS-CoV-2 (the specific virus that can cause COVID-19), or possibly a related coronavirus. Research is still underway to see if those antibodies give you protection (immunity) against getting infected again. We also don’t yet know how long any immunity may last, if immunity is possible at all.
If you have no symptoms you likely do not have an active infection and no additional follow-up is needed. However, it’s possible to test positive for antibodies even if you don’t have or never had symptoms of COVID-19. This is known as having an asymptomatic infection, or an infection without symptoms. Patients with positive tests still need to follow social distancing guidelines, wear masks while out in public and in business and practice good hand hygiene and cough etiquette.
What Does It Mean If The Test Is Negative?
If you test negative for COVID-19 antibodies, you probably did not have a previous infection. However, if you have symptoms, you could have a current infection. It’s possible that you still could get sick if you’ve had a recent exposure to the virus as antibodies don’t show up for one to three weeks after the infection takes place. This means you could still spread the virus. Some people may take even longer to develop antibodies, and some people may not develop antibodies at all.
What Are Other Uses Of Antibody Testing?
Data from antibody tests is used to estimate the total number of people who have been infected with SARS-CoV-2 in the community and helps estimate the level of herd immunity. (Herd immunity is when a high number of people are immune to a disease, therefore protecting others in that society from widespread infection.) In addition, the CDC (Centers for Disease Control and Prevention) is using antibody testing to learn more about how the virus spreads and how immune systems respond to the virus. It may also benefit healthcare workers, as well as letting people know if they could be convalescent plasma donors which is now one of the main treatment options for very sick patients.
Where Can I Get The Testing Done?
Most big labs are now offering antibody testing. If you think that you were exposed in the prior weeks, discuss this with your healthcare provider to see if you qualify for the test. Keystone Infectious Diseases is also providing appointments to discuss this option and can be reached at (717) 709-7909.
This article contains general information only and should not be used as a substitute for professional diagnosis, treatment or care by a qualified health care provider.